For nearly a century, labor strikes have been an effective tool to help unionized workers get higher wages, more benefits and greater workplace protections. But as declining union membership makes protracted strikes increasingly rare, a new model of labor agitation is emerging, and it might involve the cashier at your local McDonald’s.

On Thursday, labor organizers say workers at fast food chains like McDonald’s, Wendy’s and Burger King walked off the job or didn’t come to work in 100 cities. The strikes are the culmination of a year-long movement that began in New York last November and has spread through a series of three carefully coordinated one-day protests. The aim: an hourly wage of $15 per hour and the right to unionize. Currently, the average fast food worker earns $9 per hour, according to the Bureau of Labor Statistics. Some earn the federal minimum wage of $7.25.

The strikes are being organized by a patchwork of local labor activism groups who receive funding from the Service Employees International Union, one of the country’s largest labor unions. “The point of the one-day strike is really to show the power that workers have when they walk off their jobs and embolden more workers within the store,” says Kendall Fells, the organizing director of Fast Food Forward, the group coordinating strikes in New York. “That’s how we’ve been able to create essentially 12 months of momentum.”

With both union membership and traditional strikes on the decline, these flash tactics may be the only recourse left for labor organizers. The number of unionized laborers has decreased from 15.8 percent of the workforce in 1992 to 11.3 percent in 2012, according to the Bureau of Labor Statistics. The drop in the private sector has been even more steep, with only 6.6 percent of private sector workers currently having unionized jobs. Last year 19 large-scale work stoppages involved 148,000 workers, an increase from the nadir of the Great Recession but down significantly from a decade ago.

In the past, workers in low-skill, hourly wage jobs have been particularly hard to organize because of their replaceability. It’s hard to convince workers to sign on to a lengthy walk-out when it would almost certainly cost them their jobs. A one-day strike allows fast food employees to call attention to their cause without losing employment. Many of the workers are compensated for their lost wages from a strike fund paid for by union groups.

“It’s a pretty viable model because formal unionization is pretty close to impossible,” says Jeff Cowie, a professor of labor history at Cornell University. “If you actually want to get something done, I think these are actually pretty effective routes.”

The one-day fast food strikes have generated headlines, but they’ve yet to do much for workers’ paychecks. News reports indicated that Thursday’s strikes were a minor inconvenience at worst at many fast food restaurants, unlikely to make corporations start sweating about their bottom line. Organizers have only been able to point to wage increases of less than a dollar for a few workers following past strikes. And labor experts say the franchisee model of fast food chains, in which most of the individual restaurants are run by independent owners, makes unionization next to impossible.

Meanwhile, the National Restaurant Association, the industry’s lobbying group, contends that the entire spectacle has just been a deceptive publicity stunt that has hardly involved fast food workers at all. “These demonstrations are a coordinated PR campaign engineered by national labor groups where the vast majority of participants are activists and paid demonstrators; relatively few restaurant workers have participated in the past,” the organization said in a statement.

Fells flatly denies the allegation that demonstrators are paid to show up. “Nobody was paid to support the thousands of fast-food workers who went on strike Thursday,” he said in an email. “The industry that’s putting out that lie is the same industry that told workers to sing away stress, get a second job to make ends meet and take two vacations a year they can’t afford to reduce the risk of heart attacks.”

The strikes have helped fast food workers and their allies in the so-called living wage movement earn mindshare, dispelling the idea that they are mostly teenagers flipping burgers for pocket money. More than two-thirds of fast food workers are adults above the age of 20, according to a recent study by the University of California, Berkley. Many have been squeezed into low-wage jobs following the recession.

“As bad as the economy is today, jobs are scarce,” Dearius Merritt, a 24-year-old working at a Memphis Church’s Chicken, told TIME when he participated in the last big set of strikes in August. “These companies make too much money to hand us the crumbs that have been scattered across the floor.”

Cowie says the fast food movement has more in common with the labor strategies employed before the union era, when short strike campaigns aimed to raise awareness around issues like workplace safety. “What it actually hearkens back to is sort of a pre-New Deal paradigm. There were a lot of events that were really trying to solve issues through these pressure points…and to raise people’s awareness and change the discussion of these issues.”

By this metric, the strikes could be viewed as successful. In a Dec. 3 speech, President Obama mentioned the struggles of fast food workers while calling for an increase to the minimum wage. Democrats are currently pushing legislation that would increase the federal minimum wage to $10.10. While that’s unlikely to happen, a number of states and municipalities have recently enacted higher wage floors. And the public is on board. A recent Gallup poll found that support for a minimum wage hike from $7.25 to $9 per hour now stands at 76 percent, a 5 percentage point bump from earlier this year.

If fast food workers’ efforts help lead to an increase in the minimum wage, it might serve as model for workers in other sectors. But it’s not clear how many more one-day spectacles will be effective for fast food workers and the unions backing them.

“In the private sector, we usually don’t see these massive movements any more,” says Sylvia Allegretto, a labor economist at the Center on Wage and Employment Dynamics at the University of California, Berkeley. “You don’t know if something like this is going to fizzle out or if it’s going to keep going and gaining steam and hit a tipping point where change can actually happen.”